1. Field of the Invention
This invention relates to engine heads and in particular to high performance heads suitable for use in snow mobile type engines.
2. Prior Art
Engine heads, and heads for snow mobile type naturally aspirated and turbo charged engines are in common use and even heads milled from billet aluminum that include cooling fins are not new. Prior to the present invention, however, the inner piston opposing surfaces of available heads have failed to impart, by their design, a circular mixing motion to an air fuel mixture entering the engine combustion chamber to flow toward the center of the piston crown and for accelerating end or exhaust gases away from the piston outer perimeter to help to eliminate unwanted detonation. To provide a thorough mixing of the fuel air mixture, the invention radiuses the junction of the head squish band with the head surface that opposes the piston crown, providing a curved surface that encourages both mixing of the fuel air mixture flow and the acceleration of end or exhaust gas produced from burning of the fuel air mixture. The radiused surface encourages the fuel air mixture to circulate towards the center of the piston crown, to, in conjunction with the upward travel of the piston, produce an increase in turbulence as compared to earlier head configurations. This results in improved fuel atomization that causes a more complete fuel burning to thereby produce more power from a same volume of fuel than has been possible with earlier heads.
Applications for U.S. Design Patents have been made on two embodiments of engine heads of the invention, set out in U.S. Design patent applications Ser. Nos. 29/028,855 and 29/028,856 both filed Sep. 23, 1994.